The present invention relates generally to vasculature repair and more particularly to methods and devices for accomplishing in situ assembly of a repair device for treating abdominal aortic aneurysms.
It is well established that various fluid conducting body or corporeal lumens, such as veins and arteries, may deteriorate or suffer trauma so that repair is necessary. For example, various types of aneurysms or other deteriorative diseases may affect the ability of the lumen to conduct fluids and, in turn, may be life threatening. In some cases, the damage to the lumen is repairable only with the use of prosthesis such as an artificial vessel or graft.
For repair of vital lumens such as the aorta, surgical repair is significantly life threatening or subject to significant morbidity. Surgical techniques known in the art involve major surgery in which a graft resembling the natural vessel is spliced into the diseased or obstructed section of the natural vessel. Known procedures include surgically removing the damaged or diseased portion of the vessel and inserting an artificial or donor graft portion inserted and stitched to the ends of the vessel which were created by the removal of the diseased portion. More recently, devices have been developed for treating diseased vasculature through intraluminal repair. Rather than removing the diseased portion of the vasculature, the art has taught bypassing the diseased portion with a prosthesis and implanting the prosthesis within the vasculature. An intra arterial prosthesis of this type has two components: a flexible conduit, the graft, and the expandable framework, the stent (or stents). Such a prosthesis is called an endovascular graft.
It has been found that many abdominal aortic aneurysms extend to the aortic bifurcation. Accordingly, a majority of cases of endovascular aneurysm repair employ a graft having a bifurcated shape with a trunk portion and two limbs, each limb extending into separate branches of vasculature. Currently available bifurcated endovascular grafts fall into two categories. One category of grafts are those in which a preformed graft is inserted whole into the arterial system and manipulated into position about the area to be treated. This is a unibody graft. The other category of endovascular grafts are those in which a graft is assembled in-situ from two or more endovascular graft components. This latter endovascular graft is referred to as a modular endovascular graft. Because a modular endovascular graft facilitates greater versatility of matching the individual components to the dimensions of the patient's anatomy, the art has taught the use of modular endovascular grafts in order to minimize difficulties encountered with insertion of the devices into vasculature and sizing to the patient's vasculature.
Although the use of modular endovascular grafts minimize some of the difficulties, there are still drawbacks associated with the current methods. Where it is desirable to repair vasculature with a repair device that is assembled in situ, it can be difficult to accomplish mating the various components of the repair device. For example, it can be difficult to access an inferior opening of a bifurcated graft or repair device. That is, components that are designed to mate with contralateral limbs of a graft or repair device are sometimes difficult to align with a contralateral opening. Remote imaging techniques such as fluoroscopy provide a two dimensional display of components residing in a three-dimensional environment. Thus, gaining access to inferior openings can be a challenge. Often the challenge involves attempting to thread a guidewire through a contralateral limb opening of a repair device which later provides a track for delivering additional components designed to mate with the repair device. This challenge can also apply to any component which terminates in an opening having a smaller cross-section than the anatomy, such as a repair device with a target opening residing in an aneurysm.
Accordingly, there exists a need for methods or devices which overcome or tend to minimize the challenges associated with assembling components that have cross-sections less than the vasculature being repaired or where two dimensional imaging is found to be lacking. The present invention addresses these and other needs.